A recent trend in livestock production is the use of confinement systems for increased economical production of animal protein. We have recognized potential health hazards for agricultural workers who work in these buildings. The objective of this project is to evaluate respiratory hazards present for these workers so that appropriate control measures may be taken. Epidemiological studies have been undertaken to characterize the exposed population and quantitate the extent of the potential problem. Data collected to date suggests that there are four syndromes that workers may experience: 1) chronic irritation of the upper respiratory tract; 2) immediate hypersensitivity; 3) delayed hypersensitivity; 4) acute severe, disabling respiratory symptoms. Future epidemiological and clinical studies are designed to clarify and quantitate these early results. More specifically, the clinical studies are to characterize the health effects of the confinement atmosphere on exposed individuals, elucidate the pathophysiology of the symptoms observed, and predict the potential for chronic lung damage. The four syndroms that have been defined by the epidemiological work will be investigated individually, primarily through challenge studies. Environmental investigations will characterize the gaseous and particulate burden on the respiratory tract as well as variables affecting gas release from manure storage pits. Management practices and their relation to ambient levels of gases and dust in the work environment will be studied. Also, laboratory models of manure pits will be used to study measures to control gas release. Animal studies are being initiated to predict the chronic pathological effect of the swine confinement atmosphere on the human respiratory tract.